本文选取2011年8月2日至2019年12月31日的数据对周内效应进行检验，在选取中证全指指数代表中国股票市场整体的基础上，将股票的隔日收益拆分为隔夜收益与交易日收益，以此对检验结果进行更直观地观察。在验证了周内效应后，本文考虑规模效应并验证其与周内效应的关系。结果表明：（1）市场存在正的周二效应和负的周四效应。（2）隔日收益的整体表现与交易日收益更为相似，隔夜收益与交易日收益这两种收益的效应相互中和，交易日收益大于隔夜收益。（3）我国的周内效应中存在着规模效应

This paper selects the data from August 2, 2011 to December 31, 2019 to test the weekly effect. On the basis of selecting the China Securities All-index to represent the whole Chinese stock market, the over-day stock returns are split into overnight returns and trading day returns, so as to observe the test results more intuitively. After verifying the weekly effect, this paper considers the size effect and verifies its relationship to the weekly effect. The results show that :(1) there are positive Tuesday effect and negative Thursday effect in the market. (2) The overall performance of the over-day return is more similar to the trading day return. The effects of the overnight return and the trading day return are neutral, and the trading day return is stronger than the overnight return. (3) Size effect exists in the weekly effect in China